<template>
  <div class="article-container">
    <!-- 导航栏 -->
    <van-nav-bar
      @click-left="onClickLeft"
      class="page-nav-bar"
      left-arrow
      left-text="返回"
      title="文章详情"
    ></van-nav-bar>
    <!-- /导航栏 -->

    <div class="main-wrap">
      <!-- 加载中 -->
      <div class="loading-wrap" v-if="loading">
        <van-loading color="#3296fa" vertical>加载中</van-loading>
      </div>
      <!-- /加载中 -->

      <!-- 加载完成-文章详情 -->
      <div class="article-detail" v-else-if="article.title">
        <!-- 文章标题 -->
        <h1 class="article-title">{{article.title}}</h1>
        <!-- /文章标题 -->

        <!-- 用户信息 -->
        <van-cell :border="false" center class="user-info">
          <van-image :src="article.aut_photo" class="avatar" fit="cover" round slot="icon" />
          <div class="user-name" slot="title">{{article.aut_name}}</div>
          <div class="publish-date" slot="label">{{article.pubdate | relativeTime}}</div>
          <!-- 模板中的￥event 是事件函数 
              当我们使用v-bind向子组件传递数据，也有子组件向父组件要求修改数据
                传递：props   :is-followed="article.is_followed"
                修改：自定义事件  @update-is_followed="article.is_followed=$event"
              简写方式  使用v-model
              value='article.is_followed'
              @input="article.is_followed=$event"
          
          -->
          <follow-user :user-id="article.aut_id" class="follow-btn" v-model="article.is_followed" />
          <!-- <van-button
            :loading="followLoading"
            @click="onFollow"
            class="follow-btn"
            round
            size="small"
            v-if="article.is_followed "
          >已关注</van-button>
          <van-button
            :loading="followLoading"
            @click="onFollow"
            class="follow-btn"
            color="#3296fa"
            icon="plus"
            round
            size="small"
            type="info"
            v-else
          >关注</van-button>-->
        </van-cell>
        <!-- /用户信息 -->

        <!-- 文章内容 -->
        <div class="article-content markdown-body" ref="article-content" v-html="article.content"></div>
        <van-divider>正文结束</van-divider>
        <comment-list
          :list="commentList"
          :source="article.art_id"
          @onload-success="commentCount = $event.total_count"
        ></comment-list>
        <!-- 底部区域 -->
        <div class="article-bottom">
          <van-button
            @click="showCommentPopup=true"
            class="comment-btn"
            round
            size="small"
            type="default"
          >写评论</van-button>
          <van-icon :info="commentCount" color="#777" name="comment-o" />
          <!-- <van-icon color="#777" name="star-o" /> -->
          <collect-article :article-id="article.art_id" v-model="article.is_collected"></collect-article>

          <!-- <van-icon color="#777" name="good-job-o" /> -->
          <article-liking :article-id="article.art_id" v-model="article.attitude"></article-liking>
          <van-icon color="#777777" name="share"></van-icon>
        </div>
        <!-- /底部区域 -->

        <!-- 评论弹出层 -->
        <van-popup position="bottom" v-model="showCommentPopup">
          <comment-post :article-id="article.art_id" @post-success="onPostSuccess"></comment-post>
        </van-popup>
        <!-- /评论弹出层 -->
      </div>
      <!-- /加载完成-文章详情 -->

      <!-- 加载失败：404 -->
      <div class="error-wrap" v-else-if="errStauts === 404">
        <van-icon name="failure" />
        <p class="text">该资源不存在或已删除！</p>
      </div>
      <!-- /加载失败：404 -->

      <!-- 加载失败：其它未知错误（例如网络原因或服务端异常） -->
      <div class="error-wrap" v-else>
        <van-icon name="failure" />
        <p class="text">内容加载失败！</p>
        <van-button @click="loadArticle" class="retry-btn">点击重试</van-button>
      </div>
      <!-- /加载失败：其它未知错误（例如网络原因或服务端异常） -->
    </div>
  </div>
</template>

<script>
import { getArticleById } from '@/api/article'
import { ImagePreview } from 'vant';

import FollowUser from '@/components/follow-user'
import CollectArticle from '@/components/collect-article'
import ArticleLiking from '@/components/article-liking'
import CommentList from './components/comment-list'
import CommentPost from './components/comment-post.vue'


export default {
  name: 'ArticleIndex',
  components: {
    FollowUser,
    CollectArticle,
    ArticleLiking,
    CommentList,
    CommentPost
  },
  props: {
    articleId: {
      type: [Number, String, Object],
      required: true
    }
  },
  data () {
    return {
      article: {},
      loading: true,
      errStauts: 0,
      followLoading: false,
      commentCount: 0,
      showCommentPopup: false,
      commentList: []
    }
  },
  computed: {},
  watch: {},
  created () {
    this.loadArticle()
  },
  mounted () {
    // this.$nextTick(() => {
    //   console.log(this.$refs['article-content'])
    // })
  },
  methods: {
    async loadArticle () {
      this.loading = true
      try {
        const { data: res } = await getArticleById(this.articleId)
        // if (Math.random() > 0.5) {
        //   JSON.parse('kjsdhkjf')
        // }
        // console.log(res)
        this.article = res.data

        setTimeout(() => {
          // console.log(this.$refs['article-content'])
          this.previewImage()
        }, 0)

      } catch (err) {
        if (err.response && err.response.status === 404) {
          this.errStauts = 404
        }
        this.$toast('获取数据失败')
      }
      this.loading = false
    },
    previewImage () {
      // 得到所有的img节点
      const articleContent = this.$refs['article-content']
      const imgs = articleContent.querySelectorAll('img')
      const images = []
      imgs.forEach((img, index) => {
        images.push(img.src)
        img.onclick = () => {
          ImagePreview({
            images,
            startPosition: index,
            onClose () { }
          });
        }
      })
    },

    onClickLeft () {
      this.$router.back()
    },
    count (n) {
      this.commentCount = n
    },
    onPostSuccess (data) {
      // 关闭弹出层
      this.showCommentPopup = false
      // 将发布的内容显示到列表顶部
      this.commentList.unshift(data.new_obj)


    }
  }
}
</script>

<style scoped lang="less">
@import "./github-markdown.css";
.article-container {
  /deep/ .van-nav-bar__text,
  /deep/.van-icon-arrow-left {
    color: #fff;
  }
  .main-wrap {
    position: fixed;
    left: 0;
    right: 0;
    top: 92px;
    bottom: 88px;
    overflow-y: scroll;
    background-color: #fff;
  }
  .article-detail {
    .article-title {
      font-size: 40px;
      padding: 50px 32px;
      margin: 0;
      color: #3a3a3a;
    }

    .user-info {
      padding: 0 32px;
      .avatar {
        width: 70px;
        height: 70px;
        margin-right: 17px;
      }
      .van-cell__label {
        margin-top: 0;
      }
      .user-name {
        font-size: 24px;
        color: #3a3a3a;
      }
      .publish-date {
        font-size: 23px;
        color: #b7b7b7;
      }
      .follow-btn {
        width: 170px;
        height: 58px;
      }
    }

    .article-content {
      padding: 55px 32px;

      /deep/ p {
        text-align: justify;
      }
    }
  }

  .loading-wrap {
    padding: 200px 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: #fff;
  }

  .error-wrap {
    padding: 200px 32px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background-color: #fff;
    .van-icon {
      font-size: 122px;
      color: #b4b4b4;
    }
    .text {
      font-size: 30px;
      color: #666666;
      margin: 33px 0 46px;
    }
    .retry-btn {
      width: 280px;
      height: 70px;
      line-height: 70px;
      border: 1px solid #c3c3c3;
      font-size: 30px;
      color: #666666;
    }
  }

  .article-bottom {
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    display: flex;
    justify-content: space-around;
    align-items: center;
    box-sizing: border-box;
    height: 88px;
    border-top: 1px solid #d8d8d8;
    background-color: #fff;
    .comment-btn {
      width: 282px;
      height: 46px;
      border: 2px solid #eeeeee;
      font-size: 30px;
      line-height: 46px;
      color: #a7a7a7;
    }
    .van-icon {
      font-size: 40px;
      .van-info {
        font-size: 16px;
        background-color: #e22829;
      }
    }
  }
}
</style>
